Lensed ferrule with low back reflection

ABSTRACT

A fiber optic ferrule has an entrance surface that is angled at an angle that other than perpendicular to the optical fiber axis. The optical fibers disposed within the fiber optic ferrule are preferably separated from the entrance surface. These features reduce the amount of reflection of the light back into the optical fiber and increase the performance of the fiber optic ferrule.

REFERENCE TO RELATED CASE

This application claims priority under 35 U.S.C. § 119 (e) toprovisional application No. 62/461,073 filed on Feb. 20, 2017, and under35 U.S.C. § 120 to U.S. Pat. No. 10,585,248, issued on Mar. 10, 2020,the contents of which are hereby incorporated by reference in theirentirety.

BACKGROUND OF THE INVENTION

Existing lens ferrule designs that use single-mode optical fibers createsignificant return loss, also known as back-reflection. Within a currentlensed ferrule, light exits the fiber and if there is a gap between thefiber and ferrule, the light travels through an optically transparentadhesive, followed by several hundreds of microns of the optical polymerused to make the ferrules, and then exits the polymer ferrule material,typically through a lens. The refractive index of the polymer ferrulematerial differs significantly from the fiber, which causes the primaryreflection of light as the light transmits through the index ofrefraction change of the ferrule from the optically transparentadhesive. The light reflecting back into the optical fiber contributesto a return loss.

In order to reduce the reflection of the light back in to the opticalfiber and the ferrule itself, Applicant has determined that if thesurface of the ferrule where the light enters after leaving the opticalfiber and adhesive is disposed at an angle, the reflection can bereduced to an acceptable amount. The reflection may also be reduced ifthe front end of the optical fiber is disposed some distance from theentrance surface.

SUMMARY OF THE INVENTION

The present invention is directed to a fiber optic ferrule that includesa main body having a front end, a back end, and a middle portiondisposed between the front end and back end, a first opening through theback end of the main body, the first opening configured to receive atleast two optical fibers through the back end of the main body, aplurality of optical fiber openings disposed in the middle portion andin communication with and extending from the first opening toward thefront end, each of the plurality of optical fiber openings configured toreceive an optical fiber inserted through the back end and having alongitudinal axis, a second opening disposed between the middle portionand the front end, the second opening extending through a surface of themain body and being in communication with the plurality of optical fiberopenings, and a front portion, the front portion disposed between thesecond opening and the front end, the front portion having at least oneentrance surface that is non-perpendicular to the longitudinal axes ofthe plurality of optical fiber openings, the at least one entrancesurface being a rearward facing surface.

In some embodiments, the at least one entrance surface is in a fronthole in the front portion and is in communication with the secondopening.

In some other embodiments, the fiber optic ferrule further includes atleast one optical fiber stop, the at least one optical fiber stopconfigured to engage a front end of an optical fiber inserted through atleast one of the plurality of optical fiber openings.

In another embodiment, the at least one entrance surface comprises aflat surface having an angle of about 4 degrees.

According to another aspect of the present invention, there is a fiberoptic ferrule that includes a main body having a front end, a back end,and a middle portion disposed between the front end and back end, afirst opening through the back end of the main body, the first openingconfigured to receive a plurality of optical fibers through the back endof the main body, a plurality of optical fiber openings disposed in themiddle portion and in communication with and extending from the firstopening toward the front end, each of the plurality of optical fiberopenings configured to receive an optical fiber inserted through theback end and having a longitudinal axis, a second opening disposedbetween the middle portion and the front end, the second openingextending through a surface of the main body and being in communicationwith the plurality of optical fiber openings, a front portion, the frontportion disposed between the second opening and the front end, the frontportion having at least one entrance surface that is non-perpendicularto the longitudinal axes of the plurality of optical fiber openings, theat least one entrance surface being a rearward facing surface, aplurality of optical fibers, each of the plurality of optical fibersdisposed in respective one of the plurality of optical fiber openings,and index matching adhesive disposed in the second opening and at endsof the optical fibers.

According to another aspect of the present invention, there is a fiberoptic ferrule that includes a main body having a front end, a back end,and a middle portion disposed between the front end and back end, afirst opening through the back end of the main body, the first openingconfigured to receive at least two optical fibers through the back endof the main body, a plurality of optical fiber openings disposed in themiddle portion and in communication with and extending from the firstopening toward the front end, each of the plurality of optical fiberopenings configured to receive an optical fiber inserted through theback end and having a longitudinal axis, a second opening disposedbetween the middle portion and the front end, the second openingextending through a surface of the main body and being in communicationwith the plurality of optical fiber openings, and an entrance surfaceforming a portion of the second opening, the entrance surface beingnon-perpendicular to the longitudinal axes of the plurality of opticalfiber openings

It is to be understood that both the foregoing general description andthe following detailed description of the present embodiments of theinvention are intended to provide an overview or framework forunderstanding the nature and character of the invention as it isclaimed. The accompanying drawings are included to provide a furtherunderstanding of the invention, and are incorporated into and constitutea part of this specification. The drawings illustrate variousembodiments of the invention and, together with the description, serveto explain the principles and operations of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a cross section of one embodiment of an optical ferruleaccording to the present invention;

FIG. 2 is an enlarged view of the front end of the optical ferrule ofFIG. 1;

FIG. 3 is a schematic of the optical ferrule of FIG. 1 and the entrancesurface in the second opening thereof;

FIG. 4 shows the calculations required to determine return loss;

FIG. 5 is a graph showing the return loss for a plurality of angles andoptical fiber separation;

FIG. 6 is a view of a portion of the optical ferrule of FIG. 1 in crosssection with the optical fiber disposed against the entrance surface;

FIG. 7 is a cross section of a second embodiment of an optical ferruleaccording to the present invention;

FIG. 8 is an enlarged view of the front end of the optical ferrule ofFIG. 7;

FIG. 9 is a cross section of a third embodiment of an optical ferruleaccording to the present invention;

FIG. 10 is an enlarged perspective view of the front end of a fourthembodiment of an optical ferrule according to the present invention;

FIG. 11 is a cross section of a fifth embodiment of an optical ferruleaccording to the present invention;

FIG. 12 is a cross section of a sixth embodiment of an optical ferruleaccording to the present invention;

FIG. 13 is a cross section of a seventh embodiment of an optical ferruleaccording to the present invention;

FIG. 14 is a cross section of a eighth embodiment of an optical ferruleaccording to the present invention; and

FIG. 15 is a cross section of a ninth embodiment of an optical ferruleaccording to the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Reference will now be made in detail to the present preferredembodiment(s) of the invention, examples of which are illustrated in theaccompanying drawings. Whenever possible, the same reference numeralswill be used throughout the drawings to refer to the same or like parts.

FIGS. 1-3 illustrate one embodiment of a fiber optic ferrule 100according to the present invention. The fiber optic ferrule 100 has amain body 102 with a front end 104 and a back end 106. Between the frontend 104 and the back end 106 is a middle portion 108. The fiber opticferrule 100 has a first opening 110 through the back end 106 of the mainbody 102 to receive optical fibers 90. The fiber optic ferrule 100 has aplurality of optical fiber openings 112 disposed within the middleportion 108 of the main body 102. The plurality of optical fiberopenings 112 extend from the first opening 110 forward towards the frontend 104. The plurality of optical fiber openings 112 are configured toreceive the optical fibers 90 inserted through the back end 106. Theplurality of optical fiber openings 112 each have a longitudinal axis Aextending along the plurality of optical fiber openings 112.

The plurality of optical fiber openings 112 terminate at a secondopening 114 and are thus in communication therewith. The second opening114 is configured to receive an adhesive (preferably epoxy that has arefractive index that is the same as the core of the optical fiber) inorder to secure the optical fibers within the fiber optic ferrule 100.The second opening 114 is illustrated as opening through a top surface116 of the fiber optic ferrule 100. As would be known in the art, thesecond opening 114 could be through another surface of the fiber opticferrule 100. Preferably the longitudinal axis A of each of the pluralityof optical fiber openings 112 is parallel to the top surface 116 andperpendicular to the front face 118.

As used herein, the term “front” and “forward” means that directionwhere the fiber optic connector would mate with another fiber opticconnector or device, while the term “rear” or “rearward” is used to meanthe direction from which the optical fibers enter into the fiber opticferrule. So turning to FIG. 2, the front is the direction shown by thearrow and “back” or “rearward” is the opposite direction. Thus, thefront of the fiber optic ferrule 104 is pointed to the right in FIG. 2and the rear or rearward end of the fiber optic ferrule 104 is pointingto the left. Similarly, the top of the fiber optic ferrule 100 is thatside that has an opening into the fiber optic ferrule on the upper partof FIG. 2 while the bottom is on the bottom of FIG. 2. Further, it willbe appreciated that the optical fibers herein may be single mode ormulti-mode and, depending on the type of optical fiber, the point ofcontact of the optical fibers to the entrance surface of the ferrulewill change.

A front portion 120 is disposed between the second opening 114 and thefront end 104. The second opening 114 has a front wall 122 that definesthe boundary between the second opening 114 and the front portion 120.This front wall 122 is the entrance surface 124 of the fiber opticferrule, where the light from the optical fiber enters the front portion120 of the fiber optic ferrule 100. Thus, the term “entrance surface”relates to a surface of the front portion 120 that forms an interfacebetween the second opening 114 and the front end 104 where light crossesthe boundary between the front portion 120 and the second opening 114.Alternatively, the principles of this boundary act in the same way whenthe light travels in the opposite direction—through the fiber opticferrule and into the optical fiber. Typically, the front wall 122 isperpendicular to the top surface 116, the plurality of optical fiberopenings 112 (including longitudinal axis A), and the front end 92 ofthe optical fibers 90. The front wall 122 is also typically parallel tothe front face 118. See FIG. 1. In some fiber optic ferrules, the frontwall 122 even acts as an optical fiber stop—essentially eliminating thespace between the front end of the optical fiber and the front wall.See, e.g., FIG. 6. The front portion 120 may also have a lens 126 at thefront end 104. The lens 126 will collimate the light to allow foroptical connection of the fiber optic ferrule 100 to another ferrule,connector, or device.

In the present invention, the front wall 122 is disposed at an angle αrelative to the front face 118 and the front end 92 of the optical fiberas can be seen in FIGS. 2 & 3. As such, the front wall 122 is also nolonger perpendicular to the longitudinal axis A. The angle α ispreferably between 1 and 5 degrees. The angle α is very well controlledand is not simply a tolerance error.

In the present invention, the optical fibers 90 are also separated fromthe front wall 122 by a predetermined distance D. FIG. 3 illustratesthat the optical fiber 90 is separated from the front wall 122. Itshould be noted that even if the optical fiber 90 were to engage thefront wall 122, the core 94 of the optical fiber would still beseparated from the front wall 122 due to the angle α. Referring back toFIG. 3 and then with reference to FIG. 4, the variables used in thecalculations to determine the return loss of a fiber optic ferrule are:

λ: wavelength of the light in the optical fiber;

ω₀: effective mode radius in single mode fiber at λ, where ω₀=4.6 μm atλ=1.31 μm and ω₀=5.2 μm at λ=1.55 μm;

z: optical path (twice the distance from fiber to ferrule);

x: lateral offset between beam in fiber and beam reflected by ferrule;

ω₁: initial beam radius;

ω₂: radius of reflected beam at fiber;

T: coupling efficiency at fiber between fiber mode and reflected mode;

RL: return loss

The refractive indices (n_(i)) of the ferrule material, the fiber coreand any adhesive are also variables included in the calculation of thereturn loss.

Applicant has found that if the angle α is 5°, then the return loss is45 dB or greater. Although there is not only one return lossspecification for all connectors, 45 dB is a common requirement intoday's optical networks. See FIG. 5 showing the effect of the angle andthe optical fiber separation on the return loss.

While the angle α improves (i.e., reduces) the back reflection into thefiber, as the light transmits through the angled surface, the beam isskewed away from the angled surface and an aberration is created in thelight beam in the fiber optic ferrule 100. The top and bottom marginalrays of the light beam then go through two different optical pathlengths, which create a wavefront aberration. Such a wavefrontaberration can be compensated by making an “irregular” lens 126 that isnot rotationally symmetric about the center of the lens. Anotheraberration is created due to errors of the fiber tip cleave. If thecleave is not perfectly perpendicular to the fiber core axis, adifferent aberration is created, which is typically minimized with theindex matching material.

FIG. 6 illustrates the optical fiber 90 engaging the front wall 122 ofthe fiber optic ferrule 100. In this embodiment, the core 94 of theoptical fiber 90 is about 5 microns from the front wall 122 or entrancesurface of the fiber optic ferrule 100 because of the angle of theentrance surface. It should be noted that the bottom of the opticalfiber 90 engages the entrance surface 124 and, with the front end 92being perpendicular, the core 94 is about 5 microns from the entrancesurface 124 (for a fiber of 62.5 micron radius, 62.5×sin 5°=5) As notedin the graph in FIG. 5, the optical fiber may be disposed such that thefront end 92 is farther (in a rearward direction) from the entrancesurface 122 than 5 microns.

A second embodiment of a fiber optic ferrule 200 is illustrated in FIGS.7 and 8. The fiber optic ferrule 200 is similar to the fiber opticferrule 100 except that is has a different front end. Thus, the fiberoptic ferrule 200 has a main body 202 with a front end 204 and a backend 206. Between the front end 204 and the back end 206 is a middleportion 208. The fiber optic ferrule 200 has a first opening 210 throughthe back end 206 of the main body 202 to receive optical fibers 90. Thefiber optic ferrule 200 has a plurality of optical fiber openings 212disposed within the middle portion 208 of the main body 202. Theplurality of optical fiber openings 212 extend from the first opening210 forward towards the front end 204. The plurality of optical fiberopenings 212 are configured to receive the optical fibers 90 insertedthrough the back end 206. The plurality of optical fiber openings 212each have a longitudinal axis A extending along the plurality of opticalfiber openings 212.

The plurality of optical fiber openings 212 terminate at a secondopening 214 and are thus in communication therewith. The second opening214 also has a front wall 222 that mostly defines the boundary betweenthe second opening 214 and a front portion 220—except as noted below.The second opening 214 is configured to receive an adhesive (preferablyepoxy that has a refractive index that is the same as of the core 94 ofthe optical fiber) in order to secure the optical fibers within thefiber optic ferrule 200. The second opening 214 is illustrated asopening through a top surface 216 of the fiber optic ferrule 200. Aswould be known in the art, the second opening 214 could be throughanother surface of the fiber optic ferrule 200. Preferably thelongitudinal axis A of each of the plurality of optical fiber openings212 is parallel to the top surface 216 and perpendicular to the frontface 218.

The front portion 220 has a plurality of front holes 230, one for eachof the optical fiber openings. See FIG. 8. The front holes 230 are inline with and are a continuation of the optical fiber openings 212across the second opening 214. Each of the front holes 230 has anentrance surface 234 at the end of the front holes 230 that is alsoangled at the angle α. The end 92 of each of the optical fibers 90 arepreferably disposed within the front holes 230, but are at least 5microns from the entrance surface 234. The angle α and the distance Dare again determined by the equations in FIG. 4 as discussed above,depending on the ferrule material, the refractive index of the opticalfiber, and the like, the distance D is dependent on these factors, too.The front portion 220 may also have a lens 226 at the front end 204 tocorrect the aberrations from the angled entrance surface 234.

A third embodiment of a fiber optic ferrule 300 is illustrated in FIG. 9and has the same general construction as the other ferrules. The fiberoptic ferrule 300 has a different front end and second opening. Thefiber optic ferrule 300 has a main body 302 with a front end 304 and amiddle portion 308. The fiber optic ferrule 300 has a plurality ofoptical fiber openings 312 disposed within the middle portion 308 of themain body 302. The plurality of optical fiber openings 312 extendtowards the front end 304. The plurality of optical fiber openings 312are configured to receive the optical fibers 90 inserted through theback end 306. The plurality of optical fiber openings 312 each have alongitudinal axis A extending along the plurality of optical fiberopenings 312.

The plurality of optical fiber openings 312 terminate at a secondopening 314 and are thus in communication therewith. The second opening314 also has a front wall 322 that mostly defines the boundary betweenthe second opening 314 and a front portion 320—except as noted below.The second opening 314 is configured to receive an adhesive (preferablyepoxy that has a refractive index that is the same as of the core 94 ofthe optical fiber) in order to secure the optical fibers within thefiber optic ferrule 300. The second opening 314 is illustrated asopening through a top surface 316 of the fiber optic ferrule 300. Aswould be known in the art, the second opening 314 could be throughanother surface of the fiber optic ferrule 300. Preferably thelongitudinal axis A of each of the plurality of optical fiber openings312 is parallel to the top surface 316 and perpendicular to the frontface 318.

The front wall 322 functions as the entrance surface in this embodimentand has the angle α. The front portion 320 (and the second opening 314)has a fiber stop 330 to set the distance D to a predetermined distance.The fiber stop 330 may be an extension of the front wall 322 (i.e., madeof the same material) and formed at the same time as the rest of thefiber optic ferrule. Alternatively, the fiber stop 330 can be addedafter or machined out of the second opening 314. The fiber stop 330preferably starts at the bottom of the second opening 314 and extendsupward, but could only extend along a portion of the height of the frontwall 322 to where it would engage the bottom of the optical fiber 90.The fiber stop 330 also has an engagement surface 332 that is parallelto the end 92 of the optical fibers 90 (and also the front face 318). Asillustrated in the figures, the fiber stop 330 engage the optical fibers90 with the engagement surface 332. Thus, the fiber stop 330 engages thebottom of an optical fiber (the cladding). The light would then passover the fiber stop 330 on the way to the entrance surface of the fiberoptic ferrule 100. It would also mean that the angled entrance surfacewould only have to start above the fiber stops 330. The fiber stop 330could also be divided into a plurality of fiber stops as well.

It is also a possibility that there could also be a plurality of fiberstops 330′ adjacent one another that engage two adjacent optical fibers90. See FIG. 10. In this configuration, each of the fiber stops 330′would engage opposing sides of adjacent optical fibers 90. In thisconfiguration, the light from the optical fibers would pass between thefiber stops 330′ and the entrance surface would have to be angledbetween the fiber stops.

Another embodiment of a fiber optic ferrule 400 is illustrated in FIG.11. The fiber optic ferrule 400 has the same basic parts as the priorembodiments (e.g, main body, front end, back end, middle portion,plurality of optical fiber openings 412, second opening 414, frontportion, etc.). The fiber optic ferrule 400 has a plurality of frontholes 430. The front holes 430 are in line with and are a continuationof the optical fiber openings 412 across the second opening 414. Each ofthe front holes 430 have an entrance surface 434 at the end of the frontholes 430 that is also angled at the angle α. The front holes 430 alsohave a fiber stop 432 that is a distance D from the entrance surface434. The fiber stop 430 is a reduced diameter in the front hole 430 thatwill engage the cladding of the optical fiber 90 without blocking thelight from the optical fiber core. The angle α and the distance D areagain determined by the equations in FIG. 4 as discussed above,depending on the ferrule material, the refractive index of the opticalfiber. The front holes 430 can be filled with index matching material toassist in the transmission of the light in the front hole and across theboundary with the entrance surface.

Another embodiment of a fiber optic ferrule 500 is illustrated in FIG.12. This fiber optic ferrule 500 is similar to the fourth embodiment(fiber optic ferrule 400), but rather than having a flat surface that isangled in the prior embodiments, the entrance surface has a coneshaped-surface 532.

Another embodiment of a fiber optic ferrule 600 is illustrated in FIG.13. This fiber optic ferrule 600 is similar to the fourth and fifthembodiments (fiber optic ferrules 400/500), but rather than having aflat or cone-shaped surface of the prior embodiments, the entrancesurface has a lensed surface 630 in the front portion 620 and accessiblefrom the second opening 614. The lensed surface 630 will collimate thelight and will eliminate the need for the irregular lens of the otherembodiments.

Another embodiment of a fiber optic ferrule 700 is illustrated in FIG.14. The optic ferrule 700 has the same basic parts as the priorembodiments (e.g, main body, front end, back end, middle portion,plurality of optical fiber openings, second opening 714, front portion720, etc.). In this fiber optic ferrule, the optical fiber 790 iscleaved at an angle that is the same as, or as similar to as possible,the angle α. The optical fiber 790 is separated from the front portion720 and has an index matching adhesive or gel in the second opening 714.In this case, the index matching adhesive preferably matches the indexof the fiber optic ferrule 700 rather than the fiber core. Anyreflection of the light off the end face of the optical fiber 790 willnot reflect back into the fiber core because of the angled cleave (asindicated by an arrow off the angled cleave of the optical fiber endface). However, it is preferable to have a lens at the front end of thefiber optic ferrule 700 to correct any aberrations in the light beam asnoted above.

Another embodiment of a fiber optic ferrule 800 is illustrated in FIG.15. The basics configuration of this fiber optic ferrule are disclosedin U.S. Pat. No. 8,985,865 (the '865 patent), the contents of which areincorporated herein by reference. Fiber optic ferrule 800 also has anangled entrance surface 834 relative to the longitudinal axis A of theplurality of optical fiber openings 812 to reduce the back reflection inthis fiber optic ferrule in the same way as the other ferrules notedabove. However, in the '865 patent, the entrance surface is stillperpendicular to the longitudinal axis of the optical fiber. The lenses826 may also be irregular to correct the wavefront aberration caused bythe angled surface.

It will be apparent to those skilled in the art that variousmodifications and variations can be made to the present inventionwithout departing from the spirit and scope of the invention. Thus it isintended that the present invention cover the modifications andvariations of this invention provided they come within the scope of theappended claims and their equivalents.

We claim:
 1. A fiber optic ferrule comprising: a main body having afront end, a back end, and a middle portion disposed between the frontend and back end; a plurality of optical fiber receiving features in themain body, the plurality of optical fiber receiving features disposed inthe middle portion of the main body and configured to receive at leasttwo optical fibers; and a front portion between the middle portion andthe front end, the front portion including a first rearward facingsurface inside the ferrule at a non-perpendicular angle to alongitudinal axis of the at least two optical fibers received in themain body, said first rearward facing surface positioned inside thefiber optic ferrule such that the longitudinal axis passes therethroughand exposed to an optical medium different from that of the opticalfiber ferrule.
 2. The fiber optic ferrule according to claim 1, whereinthe first rearward facing surface forms a portion of an opening disposedbetween the middle portion and the front end.
 3. The fiber optic ferruleaccording to claim 1, wherein the first rearward facing surface is in afront hole in the front portion.
 4. The fiber optic ferrule according toclaim 1, further comprising at least one optical fiber stop, the atleast one optical fiber stop configured to engage a front end of arespective optical fiber inserted through at least one of the pluralityof optical fiber receiving features.
 5. The fiber optic ferruleaccording to claim 2, further comprising at least one optical fiberstop, the at least one optical fiber stop is a second rearward facingsurface disposed between the opening and the first rearward facingsurface.
 6. The fiber optic ferrule according to claim 4, the at leastone optical fiber stop is a plurality of second rearward facing surfacesdisposed between the second opening and the first rearward facingsurface.
 7. The fiber optic ferrule according to claim 1, wherein firstrearward facing surface comprises a flat surface having an angle ofbetween about 2 and 15 degrees.
 8. The fiber optic ferrule according toclaim 1, wherein the first rearward facing surface comprises a flatsurface having an angle of about 4 degrees.
 9. The fiber optic ferruleaccording to claim 3, wherein the first rearward facing surfacecomprises a cone shaped surface.
 10. The fiber optic ferrule accordingto claim 5, wherein the at least one fiber stop is disposed at least 20microns away from the first rearward facing surface.
 11. The fiber opticferrule according to claim 3, further comprising an optical fiber stopdisposed in the front hole.
 12. The fiber optic ferrule according toclaim 1, further comprising indexed matching adhesive disposed in theopening.
 13. The fiber optic ferrule according to claim 1, furthercomprising a lens in the front portion and associated with each of theplurality of optical fiber receiving features.
 14. The fiber opticferrule according to claim 13, where in the lens has an irregular shape.15. A fiber optic ferrule comprising: a main body having a front end, aback end, and a middle portion disposed between the front end and theback end; a plurality of optical fiber receiving features in the mainbody, said receiving features being in alignment with respectiveexternal lenses at a front end of the ferrule and configured to receiveat least two optical fibers; and a front portion between the middleportion and the front end, the front portion including a first internalrearward facing surface at a non-perpendicular angle to a longitudinalaxis of the at least two optical fibers received in the main body, saidfirst internal rearward facing surface positioned inside the fiber opticferrule such that the longitudinal axis passes therethrough and exposedto an optical medium different from that of the optical fiber ferrule.16. The fiber optic ferrule according to claim 15, wherein each end ofthe plurality of optical fibers are non-perpendicular to thelongitudinal axis of the optical fiber receiving features into whicheach optical fiber is disposed.
 17. A fiber optic ferrule comprising: amain body having a front end, a back end, and a middle portion disposedbetween the front end and the back end; means for receiving at least twooptical fibers in the main body, said means disposed at least in theback end and the middle portion of the main body; and a front portionbetween the middle portion and the front end, the front portionincluding a first rearward facing surface at a non-perpendicular angleto a longitudinal axis of the at least two optical fibers received inthe main body, said first rearward facing surface positioned inside thefiber optic ferrule in an optical path of an optical beam carried by oneor more of the at least two optical fibers.
 18. The fiber optic ferruleaccording to claim 17, further comprising a plurality of lenses inoptical alignment with the plurality of optical fiber receiving featuresto reflect light, each of the plurality of lenses having at least onesurface exposed to air.
 19. The fiber optic ferrule according to claim18, wherein the lenses reflect light from an optical fiber out through abottom surface of the fiber optic ferrule.
 20. The fiber optic ferruleaccording to claim 17, wherein an end surface of the optical fiber isnon-perpendicular to the longitudinal axis.